Upgrade pants to 1.26.0

[JustinVenus]

Changes

Minimal changes to upgrade to pants 1.26.0. Some of the noisiest deprecation messages have been addressed in this change. Next steps will be to fix the remaining deprecation messages to prepare to catch up to the latest version of pants.

Testing

% ./pants --version 2>/dev/null
1.26.0

% ./pants filter --filter-type=python_tests $(./pants list ::) | xargs ./pants test
...
20:42:01 00:05     [pytest-prep]
20:42:02 00:06     [pytest]
                   src/test/python/apache/aurora/admin                                             .....   SUCCESS
                   src/test/python/apache/aurora/client                                            .....   SUCCESS
                   src/test/python/apache/aurora/client/api                                        .....   SUCCESS
                   src/test/python/apache/aurora/client/cli                                        .....   SUCCESS
                   src/test/python/apache/aurora/client/docker                                     .....   SUCCESS
                   src/test/python/apache/aurora/client/hooks                                      .....   SUCCESS
                   src/test/python/apache/aurora/common                                            .....   SUCCESS
                   src/test/python/apache/aurora/common/health_check                               .....   SUCCESS
                   src/test/python/apache/aurora/config                                            .....   SUCCESS
                   src/test/python/apache/aurora/tools                                             .....   SUCCESS
20:42:02 00:06     [junit]
               Waiting for background workers to finish.
20:42:02 00:06   [complete]
               SUCCESS

[ridv]

LGTM, fantastic effort!